Spring powered prime mover

Abstract

An improved spring wound prime mover capable of use with toys is provided. A plastic resin housing member comprises a pair of housing shells having complementary locking pawls and keeper members to permit a snap together assembly. The housing member further supports a spring member that can be selectively connected to a gear train assembly having a first and second gear ratio. The first gear ratio includes gears with a higher degree of mechanical strength than those engaged in the second gear ratio whereby a durable gear transmission is provided that can run smooth for driving the vehicle.

What is claimed is: 
     
       1. A miniature improved spring wound prime mover capable of use in toys and the like comprising: a housing member;   an output shaft rotatably mounted to the housing member;   a spring member capable of selectively storing and releasing enery to drive the output shaft;   a plastic resin gear train assembly having a plurality of molded gears connected to the spring member and the output shaft and capable of providing a first and a second gear ratio depending on the specific gears that are engaged, the first gear ratio including gears with molded carbon fibers to provide a higher degree of mechanical strength than those engaged in the second gear ratio, the first gear ratio being engaged for moving the spring member for storing energy and to be automatically forced out of engagement when the spring member drives the output shaft and a second gear ratio automatically forced into engagement when the spring member drives the output shaft and automatically forced out of engagement when the gear train assembly is driven by an external force for moving the spring member to store energy.   
     
     
       2. The invention of claim 1 wherein the gear train assembly includes a first gear movably mounted to be automatically forced into engagement when driven by an external force to provide a first gear ratio. 
     
     
       3. The invention of claim 1 wherein the first gear ratio includes gears having a higher modulus of elasticity than the second gear ratio. 
     
     
       4. The invention of claim 2 wherein the gear train assembly includes a second gear movably mounted to be automatically forced into engagement when the spring member drives the output shaft to provide a second gear ratio and to be automatically forced out of engagement, when driven by an external force, for moving the spring member to store energy. 
     
     
       5. The invention of claim 3 wherein the first gear ratio includes gears formed of nylon and approximately 15 percent by volume of carbon fiber. 
     
     
       6. The invention of claim 3 wherein the first gear ratio includes gears having a modulus of elasticity of approximately 0.3 and the second gear ratio includes gears having a modulus of elasticity of approximately 0.25. 
     
     
       7. The invention of claim 1 wherein the housing member includes a pair of plastic resin housing shells, at least a pair of locking pawls and complementary keeper members are providing on the housing shells to permit the respective housing shells to be interlocked. 
     
     
       8. An improved spring wound prime mover capable of use in toys and the like comprising: an output shaft;   a spring member capable of selectively storing and releasing energy to drive the output shaft;   a plastic resin gear train assembly having a plurality of gears connected to the spring member and the output shaft and capable of providing a first and a second gear ratio depending on the specific gears that are engaged, the first gear ratio including gears with a higher modulus of elasticity than those engaged in the second gear ratio, the first gear ratio being engaged for moving the spring member for storing energy and to be automatically forced out of engagement when the spring member drives the output shaft and a second gear ratio automatically forced into engagement when the spring member drives the output shaft and automatically forced out of engagement when the gear train assembly is driven by an external force for moving the spring member to store energy, and   a housing member for supporting the spring member and the gear train assembly in an operative relationship, the housing member formed of a pair of plastic housing shells having between them, and extending from their respective sides, at least a pair of locking pawls and complementary keeper members to lock the respective housing shells together.   
     
     
       9. The invention of claim 8 wherein one housing shell has an integrally molded locking pawl cantilevered from each end of the shell and the other housing shell has a complementary keeper member at each end of the shell. 
     
     
       10. The invention of claim 9 wherein the locking pawl includes an enlarged locking head with a camming surface. 
     
     
       11. A spring wound prime mover capable of use in toys and the like comprising: a housing member including a first and second shell member, an intermediate plate member that divides the shell members, and locking pawls that extend from one shell member to the other, one of the shell members has a circuitous cavity with a plurality of recessed positions, the housing shell members are formed from plastic and have complementary keeper members to interact with the locking pawls to lock the respective shell members together;   an output shaft rotatably mounted to the housing member;   a spring member capable of selectively storing and releasing energy to drive the output shaft mounted in the ciruitous cavity and being removably anchored to a recessed portion, and   a gear train assembly connected to the spring member and the output shaft and capable of providing a first and a second gear ratio including a first gear movably mounted to be automatically forced into engagement when driven by an external force to provide a first gear ratio for moving the spring member for storing energy and to be automatically forced out of engagement when the spring member drives the output shaft and a second gear movably mounted to be automatically forced into engagement when the spring member drives the output shaft to provide a second gear ratio and to be automatically forced out of engagement when the gear train assembly is driven by an external force for moving the spring member to store energy, wherein the first gear ratio includes gears formed of nylon and approximately 15 percent by volume of carbon fiber to provide a higher degree of mechanical strength than the second gear ratio.